1. Field of the Invention
The invention relates to a regulation valve for a life support system for use in an aircraft cabin, in particular for life support of a pilot, crew member or a passenger in an aircraft cabin.
2. Description of Related Art
Several kinds of support systems are known for supporting pilots in an aircraft cabin. In one type of these systems a so called OBOGS (On-Board Oxygen Generating System) unit supplies the pilot with oxygen extracted from bleed air taken from the aircraft engines.
Today's life support systems for aircraft pilots with an OBOGS unit comprise a T-piece that connects a channel for breathable gas with a pressure vest. In case of rapid decompression, i.e. rapid decrease of pressure, in the aircraft cabin it is important for life support of the pilot to supply the pilot with air having a high oxygen concentration so that the pilot is prevented from getting unconscious. The air with high oxygen concentration is provided by a separate oxygen backup unit. Often, such oxygen is provided to the pilot at increased pressure to optimize oxygen uptake in the lung of the pilot. In such a case, the pilot preferably wears a tight, pressurized vest to facilitate breathing action and to prevent injuries of the chest resulting from high pressure ventilation.
Furthermore, life support systems are known comprising a non-return pressure vest valve, wherein air from inside the pressure vest is exhausted through the valve to the environment when the pilot wearing the pressure vest breathes in at a predetermined ambient pressure. When the pilot exhales, the pressure vest is filled with breathable air from the air supply. With each breathing cycle, the air in the pressure vest is partly exhausted to the environment, i.e. breathable air in the pressure vest is exchanged slightly during breathing.
However, in existing life support systems it has been observed that pilots cannot stay conscious in critical situations where a decompression event and heavy impact like Gloads occur.